Certain n-thiazol-2-ylureas

ABSTRACT

A thiazole derivative having the general formula   AND PESTICIDAL COMPOSITIONS CONTAINING THE SAME.

United States Patent [191 Guillot et al.

[ June 28, 1974 CERTAIN N-THIAZOL-Z-YLUREAS Inventors: Jean ClaudeGuillot, Eaubonne;

Pierre Poignant, Lyon; Jacques De Bazelaire de Lesseux, Rueil-Malmaison,all of France Assignee: Rhone-Priigil, Courbevoie, France Filed: Mar. 2,1976 Appl. No.: 15,900

Related US. Application Data Continuation-impart of Ser. No. 540,]92,April 5, 1966, Pat. No. 3,551,442.

US. Cl. 260/306.8 R, 71/90 Int. Cl C07d 91/46 Field of Search 260/ 306.8R

References Cited UNITED STATES PATENTS 3/1970 Driscoll 260/3068 R12/1970 Guillotetal ..260/306.8 8/1973 Guillotetal. ..260/306.8R

Primary ExaminerRichard J. Gallagher [57] ABSTRACT and pesticidalcompositions containing the same.

10 Claims, N0 Drawings CERTAIN N-THlAZOL-2-YLUREAS This is acontinuation-in-part of our copending application Ser. No. 540,l92,filed Apr. 5, 1966, and now US. Pat. No. 3,551,442.

This invention relates to a new family of compounds which arederivatives of thiazole and it relates also to the use of the thiazolederivatives as pesticides and especially as herbicides.

It is an object of this invention to produce and to provide a method forproducing thiazole derivatives of the type described and the use of suchthiazolc derivatives as a pesticide and/or a herbicide.

The thiazole derivatives embodying features of this invention may becharacterized by the formula in which X and Y are groups which may beidentical one with the other or different from each other. X and Y arerepresentative of such groups as hydrogen, halogen such as chlorine,bromine, iodine, thiocyanate, CN, COOH, an alkoxycarbonyl group, NH OH,a-hydroxyalkyl, alkyl or alkoxy group containing from 1 to 4 carbonatoms such as methyl, ethyl, propyl, butyl, ethoxy, methoxy and the likein which the hydroxyalkyl, alkyl or alkoxy group can be unsubstituted orsubstituted with a halogen, an aryl group such as phenyl, naphthyl, ahalogenated aryl group, an alkaryl group such as benzyl, tolyl and thelike, an alkoxy aryl group, a halogenated alkaryl group, a halogenatedalkoxyaryl group, an aryloxy group, a halogenated aryloxy group and analkoxyasyl group, an aryloxy group, a halogenated aryloxy group and analkaryloxy group; in which 2 is an atom selected from the groupconsisting of oxygen and sulphur; in which R is a group such as hydrogenor an alkyl, alkynyl, alkoxy, alkenyl or alkenoxy group having from 1 to4 carbon atoms, an alkylated acyl residue, at halogenated alkylated acylresidue, an aracyl, a halogenated aracyl (arylated acyl), an alkarylatedacyl, or an alkoxyaryl ocyl group; in which R and R3 is a group selectedfrom hydrogen, an alkyl group, an alkoxy group, an alkenyl group, analkenoxy group or an alkynyl group in which the groups contain from 1 to4 carbon atoms, an alkaryl residue, a halogenated alkaryl residue, anaryl group, a halogenated aryl group or an aryloxy group but in which Rand R are both hydrogen in the same compound.

The compounds defined above,.which fall within the b. The reaction of amonosubstituted carbamyl or thiocarbamyl halide, in which the halogen ispreferably chlorine, with a 2-aminothiazole in the presence of an agentwhich binds the acid liberated during the reaction in accordance withthe equation:

2. When only one of the three radicals R R and R is hydrogen, such aswhen R is hydrogen and R and R represent one of the groups of alkyl,aryl, alkaryl, halogenated alkaryl or halogenated aryl groups, thefollowing process may be employed for the preparation.

A carbamyl or thiocarbamyl halide, preferably the chloride, in which Rand R have the meaning given above, is reacted with a suitablysubstituted 2- aminothiazole in the presence of an agent that takes upthe acid liberated according to the equation:

bly the chloride R,Cl, is reacted with thiazolyl or the scope of theinvention, may be prepared by a number of synthetic methods dependingsomewhat upon the nature of the groups R R and R The following will setforth typical examples of methods for the preparation of such compounds:

1. When two of the three radicals R R or R are hydrogen, for examplewhen R, and R are hydrogen while R is an alkyl group, aryl group, oralkaryl group, a halogenated alkaryl group or a halogenated aryl group,two methods of preparation can be employed:

a. The reaction of an alkyl or aryl isocyanate or isothiocyanate with a2-aminothiazole in which X and Y are substituted groups, as illustratedin the following equation:

thiazolylthiourea derivative prepared in accordance with method (1) or(2), as illustrated by the following equation:

In the reaction outlined above, in which an acid is formed with anactive hydrogen atom, it is preferred to carry out thereactions in thepresence of an acid acceptor like a tertiary amine such astriethylamine, dimethylaniline or pyridine. p

The derivatives of thiazolylthiourea or trizolylthiourea are generallysolids which are readily soluble in The following compounds are given byway of illustration, but not by way of limitation, of the formulationsrepresenting compounds of this invention:

N-( Z-thiazolyl )-N'-methylurea; N-( 2-t hiazolyl )-N',N'-dimethylurea;N-( 2-thiazolyl )-N '-methyl-N '-methoxyurea; N-( 2-thiazolyl )-N'-phenylurea; N-( 2-thiazolyl )-N '-methyl-N-propenylurea; N-(2-thiazolyl )-N '-benzoyl-N ,N '-dimethylurea; N-( 2-thiazolyl)-N-methyl-N -phenoxyurea; N-(2-thiazolyl)-N-butenyl-N-ethylurea; N-(Z-thiazolyl )-N-trichloroacetyl-N '-butylurea; N-2 -chlorothiazolyl)-N,N -di methylurea; N-2( 5-chlorothiazolyl)-N '-methylurea; N-2( 5-chlorothiazolyl )-N -methylthiourea; N-2( 5 -chloro-4-methylthiazolyl)-N '-phenylurea; N-2( 5 -chloro-4-methylthiazolyl )-N '-methylurea;N-2( 5 -chloro-4-methylthiazolyl )-N ,N

dimethylurea; N-2( 4 ,S-dichlorothiazolyl )-N '-methylurea; N-'2( 4,5-dichlorothiazolyl )-N ,N -dimethylurea; N-2( 4-trifluoromethylthiazolyl )-N '-methyl-N methoxyurea; N-2(4-trifluorome'thylthiazolyl )-N -methylurea; N-2[4(Z-chloroethyl)thiazolyll-N -ethylurea N-2( 5 -bromothiazolyl )-N'-butynylurea; N-2( 4-chlorothiazolyl )-N '-methylurea; N-2(4-chlorothiazolyl )-N,N -dimethylurea; N-2( 4-chlorothiazolyl)-N-monochloroacetyl-N methyl N -phenyl N-2( 4-choromethylthiazolyl )-N,N -dimethylurea; N-2( 4-chloromethylthiazolyl )-N '-methylurea; N-2(S-thiocyariatothiazolyl )-N -methylurea; N-2 4-phe nyl-S-thiocyanatothiazolyl )-N propenylurea; N-2( 5-carbethoxy-4-methylthiazolyl )-N methylurea; N-2(4-2-hydroxyethylthiazolyl )-N 2,4-

dichlorophenoxy )urea; N-2( 4-methylthiazolyl )-N '-methylurea; N-2(4-methylthiazolyl )-N ,N '-dimethylurea; N-2( 5 -methylthiazolyl )-N'-phenylurea; N-2( 5 -methylthiazolyl )-N '-methylurea; N-2( 5-methylthiaz'olyl )-N',N'-dimethylurea; N-2( 4-methylthiazolyl )-N-methyl-N -methoxyurea; N-2( 4 ,5 -dimethylthiazolyl )-N '-methylurea;N-2( 4,5-dimethylthiazolyl )-N ,N -dimethylurea; N-2( 4 -methoxy-5-chlorothiazolyl )-N-acetyl-N prope nylurea;N-2(4-p-chlorophenylthiazolyl)-N-methyl-N',N-

dimethylurea; v N-2( 4-p-c hlorophenylthiazolyl )-N '-methylurea;N-2(4-p-methoxyphenylthiazolyl )-N -tolylurea.

The compounds described have been found to have exceptional herbicidalproperties. For this purpose,

they find widespread application for inhibiting the growth or evendestroying of all kinds of plants, pests, such as weeds,-brushwood andundesirable shrubbery.

The amount of the compound required to achieve the desired herbicidaleffect will depend upon a number of factors such as the nature of thecompound itself, the

resistance of the species of plants, the composition of the ground, thestate of growth of the plant at the time that treatment is effected andfinally upon the destruction desired to be effected, that is, a completekill or only a selective kill.

The compounds may thus be employed as a total herbicide or as aselective herbicide or as a growth regulator. There is a wide range ofpossible applications depending upon the chemical nature and dosage ofthe herbicidal compound utilized. The compounds may be applied eitherprior to the seeding or planting of the cultures or application can bemade as a preemergence treatment after seeding but before the culturesor weeds break through the ground or as a postemergence treatment afterthe plants break through the ground. In general, the compounds may beapplied at any stage of plant growth best adapted to the problem to besolved and the nature of the cultivated plants.

the persistence of their herbicidal action. Compounds,

of the type described, when suitably formulated, remain effective toprevent weed growth from several weeks to several months. Thiseffectiveness over a long period of time is a very desirable feature ofthe compounds of this invention since weed control can be maintainedthroughout the growing season.

Another surprising property of the compounds of this invention is thehighly'specific character oftheir action on vegetation. When applied inproper dosages, the compounds are effective to destroy certain weedswhich are dicotyledoneae without damaging other cultivated species ofdicotyledoneae. Weed plants belonging to the graminaceae family may bedestroyed in cereal cultures like wheat, barley, oats and Indian corn,without harming such cultures. The thiazolylureas and thioureas of thisinvention may be employed alone or in mixtures such as solutions inorganic solvents, or as dispersions or emulsions of the oil-in-water orwater-in? oil types or as suspensions in aqueous medium. They may beformulated into pastes or mixed with powders for dusting or they may beapplied as granules in mixtures containing talcum, kaolin, or othersuitable filler.

Such solutions, dis ersi ns; pastes, powders or granules may beformulated to contain different proportions of the active componentdepending upon the intended use. As previously described, suchcompositions may be formulated to contain the active ingredient in anamount within the range of 0.5 to percent by weight of the composition.

The compounds of this invention may also be mixed with other additiveswhich are also active or toxic with respect to plants. Certain of theseadditives may be in the form of solids, as represented by sodiumchlorate or the borates or in the form of liquids such as tar oilderivatives (creosotes), substituted or unsubstituted phenols, crude oilderivatives such as kerosene, gas oil, fuel oil and the like. Thecompounds may be formulated with other useful additives such asfertilizers which contain the usual elements of phosphorus, potassiumand nitrogen, with or without trace elements such as Fe, Mn, Zn, Mg, Coand Cu.

In accordance with an important feature of this invention, thethiazolylureas or thioureas may be combined to give a synergisticreaction with other known pesticides in the form of fungicides,bactericides, insecticides and herbicides to increase the biologicalactivity. It is possible to formulate the treating composition tocontain one or more of the pesticides described having differentchemical structures and biological activities and which may be selectedfromthe group consisting of nitrophenols, chlorophenols,chloronitrophenols, halogenated aryloxyalkylcarboxylic acids,phenylalkylcarboxylic acids, halogenated benzoic acids and derivativesthereof such as the corresponding salts, esters, amines, amides andimides, halogenated carbamates, substituted thiocarbamates andthiolocarbamates, esters of dithiocarbamic acid, alkyl isothiocyanates,monoor disubstituted amides; di-, trior tetrasubstituted aralkyl ureas,substituted triazines, aminotriazole, substituted benzothiazole,hydrazides, uracil derivatives, pyridinium salts, quaternary ammoniumsalts, inorganic herbicides such as bichromates, alkali metal cyanates,Na AsO NH SO NH etc., as represented by the following specificcompounds: pentachlorophenol; dinitrocresol; dinitrobutylphenol; Na 2,4-dichlorophenoxyacetate; Na 2,3,6-trichlorobenzoate;

Na monochloroor trichloroacetate; isopropyl N- phenylcarbamate; ethylN,N-dipropylthiolocarbamate; N,N-dimethyldiphenylacetamide;N-phenyl-N,N'- dimethylurea; 2-chloro-2,6-bis(ethylamino)-s-triazine;3-amino-l,2,4-tria zole; 2,6-dichlorobenzonitrile; maleic hydrazide;2-chlorobenzothiazole; l,l-ethylene dibromide; 2,2-bipyridinium; methylisothiocyanate.

In accordance with another feature of the invention, modifications canbe made of the various formulations to include one or more surfaceactive agents of the anionic, cationic or non-ionic types, asrepresented by: Na a]kylnaphthalenesulfonate, Na cetyl sulfate, Na oleylsulfate, Na lauryl sulfate, Na Nmethyl-N- oleyltaurate, Na oleylisothionate, Na ligninsulfonate, Na dodecylbenzene-sulfonate,alkanolamides of fatty I acids, Na di(2-ethylhexyl) sulfosuccinate,sulfonated sorbitol monooleate; the condensation product of n-' dodecylmercaptan with ethylene oxide.

The following examples of the preparation and use of the compounds ofthis invention are given by way of illustration, but not by way oflimitation:

EXAMPLE 1 Preparation of N-2(5-chlorothiazolyl)-N-methylurea To athoroughly agitated solution of 9.5 grams of 2- amino-S-chlorothiazolein 35 ml dimethyl sulfoxide (DMSO), 4.8 grams methyl isocyanate is addeddropwise with an accompanying rise in temperature to about 56 C. Whenthe addition is finished-the mixture is cooled to 45 C. and maintainedat this temperature for about 1 hour by the addition of heat, ifnecessary. The solvent is distilled off in vacuum and the residue istaken up in 500 ml of boiling acetone in the presence of vegetablecharacoal. The warm solution is filtered and white shiny crystals areformed in the filtrate upon cooling.

7: C H Cl S Compound of Example 1 3!.83 3.19 18.39 16.70

Calculated 3|.33 3.15 l8.50 16.73

EXAMPLE 2 Preparation of N-2( 5-chloro-4-methylthiazolyl )-N'-phenylurea 5 grams of 2-amino-5-chloro-4-methylthiazole is dissolvedin 50 ml of CH CN. 4.1 grams'of phenyl isocyanate is added dropwise atroom temperature with an accompanying rise in temperature to 50 C. Thistemperature is maintained for 2 hours, the mixture is cooled and theprecipitate is collected and dried. It is purified by recrystallizationfrom CH CN and decolorized in the presence of vegetable charcoal. 6.75grams of -N-2(5- chloro-4-methylthiazolyl)-N-phenylurea is obtained inthe form of a white powder having a melting point of 252 C., providing ayield of about 75 percent by weight. The compound is given the empiricalformula of cnH oclNaosi C H N Cl Compound of Example 2 49.34 3.76 15.7013.25 7

Calculated 49.46 3.62 l5 .90 13.29

EXAMPLE 3 To a suspension of 7 grams of 2-amino-5- methylthiazole in mlof Cl-l CN, 7.7 grams of phenyl isocyanate is added slowly with anaccompanying temperature rise to about 48 C. The amine becomes dissolvedduring the course of the addition and the solution is maintained at 48C. for about 20 minutes. In the course of the reaction, an insolubleproduct is produced until finally the whole mixture stiffens. Themixture is allowed to remain for about 4 hours after which the crystalsare separated and dried and washed with Cl-l CN and again dried invacuum. 12.45 grams of N- 2(S-methylthiazolyl)-N'-phenylurea is securedin the form of a white crystalline poweder having a melting point ofl196 C. corresponding to a hield of about .87..per ettl2xuri EXAMPLE 4Preparation of N-Z-thiazolyl-N'-phenylurea The procedure corresponds tothat of Example 3 except that 2-aminothiazole is employed instead of the2-amino-5-methylthiazole. The product N-2-thiazolyl- N'-phenylurea isobtained in the form of a fine white powder having a melting point ofabout 171 C. which Preparation of N-2( S-rhethylthiazolyl '-pheriylurea7 melting point is raised to 173 C. after recrystallization from CH COOHof 50% strength. The yield of crude product corresponds to about 96%.The following is the analysis of the compound as compared to theempirical formula C l-l N OS:

Preparation of N-2-thiazolyl-N'-methylurea.

To a suspension of grams of 2-aminothiazo1e in ml of CH CN, containingtwo drops of triethylamine, 6 grams of methyl isocyanate is slowly addedby pouring. The reaction is slightly exothermic and the temperaturerises to about 66 C. At the end of the addition, the mixture is cooledto 50 C. and maintained at this temperature for 1 /4 hours. TheN-2-thiazolyl-N- methylurea separates in the form of a white crystallineprecipitate which is air dried and then dried in vacuum. The yield ofcrude product, having a melting point of 215 C., is 15.45 grams or about78%. After recrystallization in absolute alcohol at C., the meltingpoint is'raised to 218 C. A final product in the form of shiny whiteneedles is obtained in an overall yield of 94%. The following is theanalysis of the compound N-2- thiazolyl-N'-methylurea produced inaccordance with this example as compared to the empirical formula C H7N3OS:

C H N 0 S Compound of Example 5 38.20 4.49 28.73 10.18 20.40

Calculated 37.77 4.35 28.84 10.52 g 20.90

EXAMPLE 6 Preparation of N-2-( 5 -thiocyanato )thiazolyl-N -methy1urea580 ml of CH CN is warmed to 80 C. and 33.6 grams of2-amino-5-thiocyanatothiazole is dissolved therein. 17.1 grams of methylisocyanate is added with constant stirring and the stirring is continuedwhile the mixture is maintained at 80 C. for 8 hours.

Upon cooling, the substituted urea precipitates in the form of a fine,slightly pinkish powder which is filtered and dried. The crudeN-2-(5-thiocyanato)thiazolyl-N- methylurea has a melting point of 225 C.and is secured in the amount of 38.9 grams or about 86.5% yield.Recrystallization in methanol yields a final product in the form ofsmall shiny flakes having a yellow coloration and a melting point of 226C.

The results of the elemental analysis of the compound as compared to theempirical formula C H N OS is set forth in the following table:

C H N S Compound of Example 6 33.63 2.82 26.15 29.92

Calculated 33.42 .74 25.96 29.90

EXAMPLE 7 Preparation ofN-2(5-carbethoxy-4-methylthiazolyl)-N-methy1urea By proceeding inaccordance with Example 1 but using as the reagents methyl isocyanateand 2-amino-4- methyl-5-carbethoxy-thiazole, the above compound isobtained having a melting point of 262 C. after recrystallization fromabsolute ethyl alcohol, corresponding to a yield of about 75.5%. Theanalysis of the compound produced furnished the following valuescompared to the empirical formula C H N O S:

C H N O 5 Compound of Example 7 44.43 5.38 17.27 19.72 13.17

Calculated 44.03 4.83 17.44 19.92 13.50

EXAMPLE 8 Preparation of N-2(4-methylthiazolyl)-N'-methylurea Theprocedure of Example 5 is followed but in which the reagents are methylisocyanate and 2-amino-4- methylthiazole. The above compound is obtainedin a yield of 93% having a melting point of 212 C. afterrecrystallization from CH CN.

The results of the analysis of the compound produced by the example ascompared to the empirical formula C H N OS is as follows:

C H N 0 5 Compound of Example 8 42.09 5.30 24.54 9.34 18.73

Calculated 41.81 5.08 24.83 9.32 18.67

EXAMPLE 9 Preparation of v N-2( 4-trifl uoromethylthiazolyl )-N'-methylurea c H N F s Compound of Example 9 32.00 2.69 18.66 25.3114.24

Calculated 32.23 2.88 18.76 14.45

' flux and then it is cooled and poured into an excess of EXAMPLE 1OPreparation of I N-2(4-p-chlorophenylthiazolyl )-N-methylurea C H Cl N SCompound of Example l 49.34 3.76 l3.24 .l5.69 ll.97

Calculated 49.!6 3.64 13.30 15.52 I 1.96

EXAMPLE 1 1 Preparation of N-2( 5-chloro-4-methylthiazolyl)-N-methylureaA mixture of 6.1 grams of 2-amino-5-chloro-4- methylthiazolechlorohydrate and 25 ml pyridine is heated to 3540 C. 2.1 grams ofmethyl isocyanate is added over a period of minutes. The mixture isheated with stirring for 3 hours to 50 C. and it is then cooled andrapidly poured over 500 grams of ice. The precipitate formed is filteredand recrystallized from CH CN. A yield of 75% is obtained of thecompound N-2(5-chloro-4-methylthiazolyl)-N'-methylurea in the form of awhite powder having a melting point of 237 The analysis of the compoundas compared to the empirical formula C H ClN OS is as follows:

Preparation of N-2( 5-chlorothiazolyl)-N '-methylthiourea 1.5 grams ofmethyl isothiocyanate and 2.7 grams of 2-amino-5-chlorothiazole aredissolved in 42 grams pyridine. The solution is heated for 5 hours underrewater.

The formed precipitate is filtered, thoroughly washed with water anddried. The N-2(5-chlorothiazolyl)-N- methylthiourea that is obtained isrecrystallized from acetone in the presence of vegetable charcoal toproduce the compound which melts at 199 C.

The following is an analysis of the compound as compared to theempirical formula C H ClN S c H v N 01 5' Compound of Example 12 28.912.91 20.23 I706 30.27

Calculated 29.56 i 3.0 20.17 16.59 31.12

EXAMPLE 13 Preparation ofN-2(5-chloro-4-methylthiaz0lyl)-N',N-dimethylurea 38.4 grams of pyridineis mixed with 22.7 grams dimethylcarbamyl chloride and cooled to 5 C.29.7 grams of2-amino-5-chloro-4-methylthiazole is added in smallincrements. The reaction is slightly exothermic so that the temperaturerises to about 16 C. The materials are allowed to stand for 1 hour andthen heated for 3 hours at C. The mixture is then allowed to cool andpoured into 1 liter of ice water with thorough stirring so as to preventthe formation of lumps. The product N-2(5-chloro-4-methylthiazolyl )-N 1dimethylurea is separated by filtration and recrystallized from 1.5liters of CH COOl-l of 50% strength. The crystals are washed with wateruntil made neutral and the resulting compound obtained in a yield of42.5% has a melting point of l63 C. I

The analysis of the compound as compared to the empirical formula C l-lClN OS is as follows:

C H Cl S Compound of Example [3 38.26 4.59 l6.l5 I459 Calculated 38.294.22 16.15 .l4.59

EXAMPLE l4 Preparation of N-2( 4,5-dimethylthiazolyl )-N '-methylureaCompound of Example 14 45.38 5.98 22.67 8.63

Calculated 45.33 5.66 22.97 8.83

EXAMPLES 15-20 Biological experiments and tests were conducted withvarious greenhouse plants using N-2(5- chlorothiazolyl)-N'-methylurea infour different dosages, as set forth in the following tables. Twotechniques of treatment were employed, as follows a. the pre-emergencetreatment. i.e. after seeding but before the plants break through theground (see Tables 1 to 3);

b. the post-emergence treatment, i.e. after the plants have brokenthrough the soil, when each seed has 1 1 developed into a young plant ofbetween 5 to 15 cm in height (see Tables 4 to 6). The active product wasformulated into an aqueous In Table 3, the active product is applied inthe form of a sludge containing 5% by weight of a wettable powder ofN-2(5-chl0rothiazolyl) N'-methylurea.

TABLE 3 Plant species treated Results after 10 days doses in kg/hectareof active material Results after 30 days doses in kg/dectare of activematerial Mustard (wild) (Sinapis arvensis Great nasturtium (Tropaeolummajus, variety Nanum) Oats (Avena sativa) TABLE 1 I Pre-emergencetreatment of several plants which belong to the graminaceae and werecultivated in a greenhouse, the results and evaluations being made 37days after treatment:

Species of treated plants doses in kg/hectare of active material Barley(Hordeum 0 l5 l5 l00 distichum) lndian corn (Zea mays) 0 80 Oats (Avenasativa) 0 20 100 I00 Wheat (Triticum vulgare) 0 35 100 100 Wild oats(Avena fatua) 5 I00 100 Wild millet (Echinochloa 5 65 98 98 crusgalli)Millet (Panicum 5 88 100 I00 miliaceum) Rye-grass (Lolium 75 98 100 I00italicum Slender Foxtail 90 100 100 100 (Alopecurus agrestis) TABLE 2Pre-emergence treatment of various plants which are dicotyledoneae andwere cultivated in a greenhouse. the evaluations being made 37 daysafter treatemnt:

doses of the active Species of plant treated material in kg/hectare Peas(Pisum sativum) O 0 0 3 Tomatoes (Solarium 0 0 0 95 esculentum) Carrots(Daucus I5 I00 I00 I00 carotta) Linseed',(linum 20 I00 100 100usitatissimum Buckwheat (Polygonum 98 98 I00 I00 fagopyrum) Amaranth(Amaranthus 98 100 I00 100 species) Rape (Brassica napus) 100 I00 I00100 For the great nasturtium, as recognizable from this table, nodestruction occurred, but a slight phytotoxicity was noted starting withthe dosage of 10 lag/hectare of the active material.

Tables 1 to 3 show that N-2(5-chlorothiazolyl)-N- methylurea hasexceptional herbicide effect which can destroy species belonging both tothe graminaceae as well as to the dicotyledoneae. Thus it is applicableagainst a wide spectrum of plants. Furthermore, this herbicide enjoysexceptional efficiency because it is able to destroy up to 100% of suchspecies such as slender foxtail, rape and buckwheat when employed indosages as low as 0.5 kg/hectare in the pre-emergence treatment. Thiscompound also exhibits a selective herbicidal action due to anunexpected and remarkable fact. For example, when applied in the dosageof 0.5 kg/hectare, 90% of the foxtail is destroyed whereas the wheatremains undamaged. This herbicide shows a good selectivity with respectto peas and tomatoes in pre-emergence .treatment, whereas, at the samedosage, other dicotyledoneae such as carrots, linseed and rape arecompletely destroyed. At dosages of 4 kg/hectare, all of the test plantswiththe exception of the peas and the great nasturtium, are practicallydestroyed. Of considerable interest is the fact that the compound canfunction as a total weed removal agent.

The following tables 4 and 5 present the results of post-emergencetreatments of various plants'which are, respectively, graminaceae inTable 4 and dicotyledoneae in Table 5. The experiments were undertakenon greenhouse cultures with a wettable powder containing 20% of theactive ingredient N-2(5-chlorothiazolyl)- N'-methylurea. The evaluationsset forth in the tables were made 34 days after treatment.

TABLE 4 Species of plant Doses per hectare. in kg treated of activematerial Wheat 0 0 0 0 Barley 0 0 0 0 Wild cats 0 0 0 l0 Oats 0 0 0 20Indian corn 0 0 0 25 Rye grass 5 96 Slender foxtail I0 92 98 98 Wildmillet 80 100 I00 I00 TABLE 5 Species-of plant Doses per peetare. in kgof treated active material Peas 0 0 0 Rape 0 0 0 5 Linseed 5 70 Carrots5 80 98 Buckwheat I5 TABLE 6 Post-emergence treatment of various plantswith aqueous dispersions containing 5% by weight of the active material:

Species Doses per of hectare in Wild Great Oats plant kg of activeMustard Nasturtium treated material 2.5 0 0 0 Results 5 0 0 0 after IO80 0 l5 I0 l5 80 O 20 days: 20 80 20 30 8O 0 20 2.5 100 0 0 Results 5I00 0 20 after I0 I00 0 one 15 I00 0 I00 month: 20 I00 I00 30 I00 0 I00It will be recognized from the above table thatfor the great nasturtiumno destruction occurs at any of the dosages although a slightphytotoxicity appears with the dosage of IO kg/hectare of activematerial.

The results set forth in Tables 4 to 6 indicate that post-emergencetreatment with the herbicide destroys 92% of the slender foxtail whenapplied in a dosage of l kg/hectare and that it is still fully selectivein that it does not destroy wheat, barley and wild oats even at twicethe dosage. At a dosage of 2.5 kg/hectare, wild mustard is completelydestroyed within one month after treatment whereas oats remainsunaffected.

EXAMPLES 21-23 Field experiments were conducted with N-2(5-ehlorothiazolyl)-N-methylurea as the active material applied to theplants in the same manner as described in Examples 15-20.

a. Barley in spring At the stage of development of three leaves, barleyis treated by applying 0.75 to 1.25 kg/hectane of active material. Theaccompanying weeds were represented by goosefoot (Chemopodium species)and by wild radish (Raphanus raphanistrum). The effectiveness of weedremoval was very good 64 days after treatment.

. perfect in that 45 days after treatment, the herbicidal efficiency wasexhibited by the fact that knotweed Polygonum aviculare), black bindweed(Polygorium convulvulus) and goosefoot (Chemopodium species) werecompletely destroyed without harm to the pea plants.

EXAMPLES 24-27.

The biological activity of N-2(5-chloro-4- methylthiazolyl)-N-methylureaupon various plants in the greenhouse was tested with four differentdosages, as indicated in the following tables. Two different treatmentswere employed, namely, a pre-emergence treatment after the seeding butbefore the plants broke through the ground, a post-emergence treatmentafter the plants had broken through the ground and when each plant waspresent as a young plant (seedling) which was approximately between 5 to15 cm in height.

The active material was applied by spraying from an aqueous suspensioncontaining 20% by weight of the active material as a wettable powder.The results observed are expressed in the following table in percent ofdestruction of the treated plants.

TABLE 7 Pre-emergence treatment of various plants which are graminaceae.setting forth observations 4I days after treatment Pre-emergencetreatment of various dicotyledoneae. observations being made 41 daysafter treatment Species of Doses in kg/hectare of treated pl an t s Aactive materials Peas 0 0 0 0 Green bean (Phaseolus O Y 0 0 0 vulgaris)Tomatoes I 0 0 0 25 Common sunflower 0 5 0 35 (Helianthus annuus)Buckwheat 0 0 5 40 Rape 0 0 10 98 Linseed 0 65 I00 I00 Carrots 0 98 I 00I00 The following tables 9 and I0 set forth the results frompost-emergence treatments of various graminaceae in Table 9 anddicotyledoneae in Table I0, in the greenhouse. The results are thoseobserved 42 days after treatment.

TABLE 9 tive material. In the pre-emergence treatment, a selective weedkilling is observed in that wheat, Indian corn, Species of Doses inkg/hectare of green beans and peas remain undamaged (Tables 7 and nt jmgtenals 8 8) whereas the slender foxtail is destroyed in the amounts of55-95% and the Italian wild rye grass in the mgi i un co n 8 g 8 8amounts of 90-100%. In the post-emergence treat- Bl wild Mine 0 0 20 3oment, a selective weed killing IS obtained without harm Oats 0 0 30 100to Indian corn and peas (Tables 9 and while foxtail :32? 8 8 Q8 38 10 isdestroyed in amounts up to 70-90% and wild rye Wheat 0 24 50 9s grass inamounts up to 95l00%. Italian wild rye grass 0 70 95 I00 EXAMPLES 28-33TABLE 10 According to the method used in Examples 15-20, Species ofDoses in kg/hectare of the biological activity of several substitutedthiazolylu- Plants treated i mglenals 4 8 reas which form the subjectmatter of this invention were tested with respect to plants using adosage of 8 :eas 1 8 8 8 2O kg/hectare of active material. Tables 1 Iand 12 set jgg 0 0 so forth the results obtained, expressed in percentde- Green beans 0 40 struction of .the treated plants.

TABLE- I 1 Pre-emergence treatment of various graminaceae in which theresults set forth were observed 46 days after treatment Examples 28 2930 Active material N-2(4-methyl- N-2(5-chloro- N-2(4-tr fluorotestedthiazolyl )-N 4-methylthiamethylthlazolyl methylurea Z0lyl)-N',N'N'-rnethylurea dimethylurea Indian Species corn 0 O 0 Wheat 0 0 ofBarley 0 -0 20 Oats 20 0 90 plants Millet 0 20 100 Wild Millet 10 so 20treated Wild rye 20 60 Foxtail 40 95 98 TABLE I2 Pre-emergence treatmentof various dicotyledoneae, in which the results were observations made46 days after treatment Examples 3l 32 33 Active material N-ZM-methyl-N-2(5-chloro-4- N-2(4-trifluorotested thiazolyl(-N'-methylthiamethylthiazolyhmethylurea zolyl)-N',N'- Nt thyl readimethylurea Species Peas 20 0 95 of Green beans 0 0 7O plant Sunflower95 0 I00 tested Tomatoes 20 40 I00 Buckwheat 90 30 100 Rape 60 I00Linseed 95 95 I00 Carrots 98 I00 I 00 8 v g8 28 g8 60 Examples 29 and 32show that treatment is selective Linseed 60 60 in that it does notdestroy wheat, Indian corn, oats and Carrots 60 so 90 x00 barley, greenbeans, peas and sunflower, whereas destruction is observed of slenderfoxtail up to 95%, Italian wild rye grass up to 70% and wild, millet upto 80%.

The compounds of Examples 30 and 33 show herbicidal activity but withouttoo much selectivity. All of the millet and rape are destroyed and onlyIndian corn remains fully resistant.

The compounds of Examples 28 and 31 are selective in that wheat, Indiancorn, millet, barley and green beans are not destroyed while herbicidaleffect in the order of 85% is secured with respect to rape.

EXAMPLE 34 Treatment is effected in accordance with Examples 15-20 butat a dosage of kg/hectane, using as the active ingredientN-2-thiazolyl-N'-methylurea. The active ingredient completely destroyedmillet in a preemergence treatment.

EXAMPLE 35 Preparation of N-(S-cyano 2-thiazolyl)N-methylurea c H N sTheoretical 39.55 3.32 30.75 17.60

Experimental 39.41 3.25 30.67 17.52

EXAMPLE 36 Preparation of N-(S-methyl-Z-thiazolyl)N'-methylurea Usingthe same procedural steps as in Example 5 except that the reactants are2-amino-5-methyl-thiazole and methyl isocyanate, a compound of meltingpoint in the range 2l0-2l5 C. is obtained with a 75% yield.

The analysis for C H N OS is the following:

Preparation of N-( 4-chloromethyl-2-thia2olyl)N'-methylurea 3 grams of2-amino-4-chloromethyl thiazole hydrochloride are dissolved in 30 ml ofwater. To this solution 0.77 grams of methyl isocyanate followed up by1.8 grams of sodium carbonate dissolved in 50 cc. of water are added.

After 24 hours, the insoluble phase which is constituted of the freeamine which has not reacted is filtered, and the filtrate is evaporatedto dryness and the residue isrefluxed with acetone. After heatfiltering, the solution is evaporated to dryness, 2 grams of a pastyreddish mass which is not distillable is obtained, the structure ofwhich is confirmed by nuclear magnetic resonance measurement.

EXAMPLE 38 Preparation of N-(4-methyl-2-thiazolyl)N, N'-dimethylurea 25grams of 2-amino methyI-4-thiazole are dissolved in 24 g of dimethylcarbamyl chloride to which 22 grams of triethylamine are added. Thereactants are left two days in contact. A great excess of water is thenadded and extraction with ethylalcohol is effected.

After having removed the solvent, a brown reddish oily residuecorresponding to the desired compound as shown by its nuclear magneticresonance spectrum is obtained.

EXAMPLE 39 Preparation of N-(4,5-dimethyl-2-thiazolyl)N',

N'-dimethylurea Using the method of Example 13. the reagents beingpyridine, dimethylcarbamyl chloride and Z-amino 4,5- dimethyl thiazole,a compound melting at 201 C. after being recrystallized in acetonitrileis obtained with a 45% yield.

The analysis for C H N OS is the following:

C H S N Theoretical 7c 48.21 6.57 16.09 21.09

Experimental 7c 48.63 6.44 16.03 21.47

EXAMPLE 40 Preparation of N-(4,5-diethyl-2-thiazolyl)N'-methylurea Usingthe same procedural steps as in Example 5 except that the reactants are2-amino-4,5-diethyl thiazole and methyl isocyanate, a compound ofmelting point 185 C. crystallizing in the form of white flakes isobtained with an 89% yield.

It will be seen from the foregoing that a new series of compounds areprovided which have shown marked activity as a herbicide in managingplant growth and in the destruction of undesirable weeds and plantsconnected with plant growth. The compounds of this invention exhibit animportant degree of selectivity with respect to their herbicidalactivity with various plants and combinations of plants.

It will be understood that changes may be made in the details offormulation and application without departing from the spirit of theinvention, especially as defined in the following claims.

We claim: 1. A thiazole derivative having the formula T; SN 1 Z yh eiswherein X and Y are each selected from the group con-- 1-4 carbon atomsand alkenyl containing 2-4 carbon atoms, R and R are each selected fromthe group consisting of hydrogen, alkyl containing l-4 carbon atoms,alkenyl containing 2-4 carbon atoms and alkynyl containing 2-4 carbonatoms, and Z is selected from the group consisting of sulphur andoxygen.

2. A thiazole derivative as claimed in claim 1 in which the compound isN-Z-thiazolyl-N'-methylurea.

3. A thiazole derivative as claimed in claim 1 in which the compound isN-2(5-carbethoxy-4-. methylthiazolyl)-N'-methylurea.

4. A thiazolc derivative as claimed in claim 1 in which the compound isN-2(4-trifluoromethylthiazolyl)-N'-methylurea.

N-2( 5-chloro-4- 9. A thiazolc derivative N-2(4-mcthylthiazolyl)-N-methylurca.

10. A thiazolc derivative N-2-thiazolyl-N- phenylurea.

2. A thiazole derivative as claimed in claim 1 in which the compound isN-2-thiazolyl-N''-methylurea.
 3. A thiazole derivative as claimed inclaim 1 in which the compound isN-2(5-carbethoxy-4-methylthiazolyl)-N''-methylurea.
 4. A thiazolederivative as claimed in claim 1 in which the compound isN-2(4-trifluoromethylthiazolyl)-N''-methylurea.
 5. A thiazole derivativeas claimed in claim 1 in which the compound isN-2(4-p-chlorophenylthiazolyl)-N''-methylurea.
 6. A thiazole derivativeN-2(5-chloro-4-methylthiazolyl)-N''-phenylurea.
 7. A thiazole derivativeN-2(5-methylthiazolyl)-N''-phenylurea.
 8. A thiazole derivativeN-2-(5-thiocyanato)thiazolyl-N''-methylurea.
 9. A thiazole derivativeN-2(4-methylthiazolyl)-N''-methylurea.
 10. A thiazole derivativeN-2-thiazolyl-N''-phenylurea.